Development of the Heart Flashcards
……… gives rise to almost all heart components
splanchnopleure
angiogenesis refers to ………
Development of blood and blood vessels
By day ………., the lateral mesoderm has somatopleure and splanchnopleure
18
When does the vascular system appear?
By the middle of the third week
Describe the formation of the primary heart field
Progenitor heart cells lie in the epiblast, immediately adjacent to the cranial end of the primitive streak. From there, they migrate through the streak and into the splanchnic layer of lateral plate mesoderm where they form a horseshoe-shaped cluster of cells called the primary heart field (PHF) cranial to the neural folds
the progenitor heart cells migrate and form the PHF during days …….
days 14 to 16
Outlist the parts of the heart derived from the PHF
- the atria
- left ventricle
- most of the right ventricle
Mention the remaining parts of the heart derived from the secondary heart fold
part of the right ventricle
outflow tract (conus cordis and truncus arteriosus)
………….. form part of the aorta and pulmonary artery
conus cordis and truncus arteriosus
The SHF is regulated by …………. that control concentrations of FGFs
neural crest cells
the cardiac tube begins to bend on day ………
23
The bending of the cardiac tube creates the …………..
cardiac loop.
The bulbus cordis is narrow except for its………..
proximal third
…………… will form the trabeculated part of the right ventricle
Bulbus cordis
………….. will form the outflow tracts of both ventricles.
conus cordis
The distal part of the bulbus, the truncus arteriosus will form ……………..
the roots and proximal portion of the aorta and pulmonary artery
The junction between the ventricle and the bulbus cordis, externally indicated by the …………..
bulboventricular sulcus
………… is called the primary interventricular foramen
bulboventricular sulcus
……………. begins to form primitive trabeculae at the end of loop formation
the smoothwalled heart tube
the smooth-walled heart tube begins to form primitive trabeculae in two sharply defined areas, namely
proximal and distal to the primary interventricular foramen
the trabeculated proximal third of the bulbus cordis is called the …………….
primitive right ventricle
What is dextrocardia?
A condition where the heart lies on the right side of the thorax instead of the left.
What is the cause of dextrocardia?
It occurs when the heart loops to the left instead of the right.
Dextrocardia may be induced during gastrulation when laterality is established
Situs inversus refers to ………….
A complete reversal of asymmetry in all organs
The conotruncal portion of the heart tube, initially on the right side of the pericardial cavity, shifts gradually to a more medial position. This change in position results from ……………….
The formation of two transverse dilations of the atrium, bulging on each side of the bulbus cordis
The heart is derived from a part of the mesoderm called the ……….
Visceral mesoderm
Right and left viteline veins fuse to form ……….
Sinus venosus
By ………….. week the primitive heart reaches the thorax
The beginning of the fourth week
The primitive ventricle and primitive atrium are separated by …………
Atrioventricular sulcus
The the left and right atrium are derived from ………….
Primitive atrium
The left ventricle is derived from …………
The primitive ventricle
The Bulbus cordis gives rise to ……….
The right ventricle and outflow tracts
………… grows downward to create two separate chambers, and close the ostium primum
Septum primum
……….. is referred to as the first opening
Ostium primum
After the septum secundum covers the ostium secundum a small opening called ……………. Is left
Foramen ovale
A hole that appears in the upper area of the septum primum is called …………
Ostium secundum
What is the function of foramen ovale?
allows oxygenated blood to bypass the pulmonary circulation from the right atrium to the left during foetal life
The SHF appears on days ……..
20 to 21
The SHF resides on ………..
The splanchnic mesoderm ventral to the posterior pharynx
Cells of the PHF are induced by ……….
Cells of the PHF are induced by the underlying pharyngeal endoderm to form cardiac
How are the dorsal aortas formed?
Other blood islands appear bilaterally, parallel, and close to the midline of the embryonic shield, forming a pair of longitudinal vessels called the dorsal aortae.
How are the endocardia’s tubes formed?
the blood islands unite to form the right and left endocardial tubes in the cardiogenic region
The cephalic portion of the cardia tube bends ………
ventrally, caudally and to the right
The caudal portion (atrial portion) of the cardiac tube shifts ………
dorsocranially and to the left
The cardiac loop formation ends on day …….
Day 28
Why does the cono-truncal portion of the heart tube shift gradually to a more medial position?
This is as a result of two transverse dilations of the atrium on each side of the bulbus cordis
the epicardium is formed from ……..
Pro-epicardium and mesothelial cells in the outflow tract
Coronary arteries originate from……..
The endocardium/visceral pericardi
Mention the 5 dilations formed from the heart tube (from caudal to cranial)
sinus venos
atrium
ventricle
bulbus cordis
truncus arteriosus
The smooth part of the right atrium is formed from ……..
Sinus venosus
Mention the 3 adult structures of the heart formed from the sinus venosus
-Smooth part of the right atrium
- Coronary sinus
- oblique vein of the left atrium
The trabeculated parts of right and left atria are formed from ……
The primitive atrium
The trabeculated part of left ventricle is formed from ……….
Primitive ventricle
The trabeculated part of the right ventricle is formed from ……..
Bulbus cordis
Mention the adult structures of the heart formed from the bulbus cordis
- Trabeculated part of right ventricle (proximal Cordis) - Outflow part of both ventricles(distal part, Cordis)
The root & proximal part of the aorta are formed from …….
Turncus arteriosus
